The Public Service Platform for Industrialization Development Technology of Marine Biological Medicine and Products of the State Oceanic Administration, Center of Engineering Technology Research for Microalga Germplasm Improvement of Fujian, Fujian Key Laboratory of Special Marine Bioresource Sustainable Utilization, Fujian Key Laboratory of Developmental and Neural Biology, Southern Institute of Oceanography, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.
Fujian Fishery Resources Monitoring Center, Fuzhou 350003, China.
Genomics Proteomics Bioinformatics. 2022 Dec;20(6):1138-1153. doi: 10.1016/j.gpb.2022.05.010. Epub 2022 Aug 13.
Isochrysis galbana is considered an ideal bait for functional foods and nutraceuticals of humans because of its high fucoxanthin (Fx) content. However, multi-omics analysis of the regulatory networks for Fx biosynthesis in I. galbana has not been reported. In this study, we report a high-quality genome assembly of I. galbana LG007, which has a genome size of 92.73 Mb, with a contig N50 of 6.99 Mb and 14,900 protein-coding genes. Phylogenetic analysis confirmed the monophyly of Haptophyta, with I. galbana sister to Emiliania huxleyi and Chrysochromulina tobinii. Evolutionary analysis revealed an estimated divergence time between I. galbana and E. huxleyi of ∼ 133 million years ago. Gene family analysis indicated that lipid metabolism-related genes exhibited significant expansion, including IgPLMT, IgOAR1, and IgDEGS1. Metabolome analysis showed that the content of carotenoids in I. galbana cultured under green light for 7 days was higher than that under white light, and β-carotene was the main carotenoid, accounting for 79.09% of the total carotenoids. Comprehensive multi-omics analysis revealed that the content of β-carotene, antheraxanthin, zeaxanthin, and Fx was increased by green light induction, which was significantly correlated with the expression of IgMYB98, IgZDS, IgPDS, IgLHCX2, IgZEP, IgLCYb, and IgNSY. These findings contribute to the understanding of Fx biosynthesis and its regulation, providing a valuable reference for food and pharmaceutical applications.
球等鞭金藻（Isochrysis galbana）由于其富含岩藻黄质（Fx），被认为是功能性食品和人类营养保健品的理想饵料。然而，关于球等鞭金藻 Fx 生物合成调控网络的多组学分析尚未见报道。本研究报道了球等鞭金藻 LG007 的高质量基因组组装，其基因组大小为 92.73 Mb，contig N50 为 6.99 Mb，包含 14900 个蛋白编码基因。系统发育分析证实了甲藻门的单系性，球等鞭金藻与菱形海线藻（Emiliania huxleyi）和黄藻（Chrysochromulina tobinii）亲缘关系最近。进化分析表明，球等鞭金藻和菱形海线藻的分化时间约为 1.33 亿年前。基因家族分析表明，脂质代谢相关基因显著扩张，包括 IgPLMT、IgOAR1 和 IgDEGS1。代谢组学分析表明，在绿光下培养 7 天的球等鞭金藻中类胡萝卜素的含量高于白光下，且β-胡萝卜素是主要的类胡萝卜素，占总类胡萝卜素的 79.09%。综合多组学分析表明，绿光诱导可增加β-胡萝卜素、玉米黄质、叶黄素和 Fx 的含量，这与 IgMYB98、IgZDS、IgPDS、IgLHCX2、IgZEP、IgLCYb 和 IgNSY 的表达显著相关。这些发现有助于了解 Fx 的生物合成及其调控机制，为食品和制药应用提供了有价值的参考。
